1. Field of the Invention
The invention concerns a stapler with a base part carrying an anvil in its front area, with a staple magazine limitedly pivotable about a transverse axis on a mounting block in the rear area of the base part, with a staple pusher guided slideably in a slide guide of the staple magazine and spring biased towards to the head part thereof, with a cap part limitedly pivotable about the transverse axis relative to the staple magazine and relative to the base part, forming or including a magazine cover, the cap part carrying a driver which has a punch stroke extending into the head part of the staple magazine, and wherein the cap part, while taking along the staple pusher, and the staple magazine are slideable relative to each other between an operating position and a loading position, and with a locking mechanism for connecting the cap part with the staple magazine releaseably, fixed against sliding, in the operating position.
2. Description of the Related Art
Staplers of this type are known (DE-A 44 47 079), which include a spring compartment magazine, in which a magazine insert is slideable, relative to the base part and to the cap part, from an operating position into a loading position. The magazine insert, which is spring-biased, is pressed out of the rear side of the upper part into a loading position by operation of a push button or key. Spring compartment devices are somewhat more complex in their construction than so-called upper loading devices, of which the cover part is pivoted 180xc2x0 about the transverse axis into a loading position for the refilling thereof and thereby the staple pusher is taken along against a spring force in the push guide of the staple magazine. The retraction of the pusher occurs thereby either via a pull spring or a pull slide bar. In both cases the cap part is under the direct or indirect influence of the spring which is acting upon the staple pusher, which is attempting to pivot the cap part back to its closed position. In order to prevent an undesired return pivoting of the cap part, it is releaseably locked to the base part in its folded-open loading position by means of a detent mechanism.
Beginning therewith, the present invention is concerned with the task of developing a stapler of the above described type, which comprises a loading mechanism which is simple to operate and easy to manufacture.
The inventive solution is based on the concept, that the staple magazine should be connected fixed against sliding with the base part, and that the cap part, in certain cases together with the magazine cover, should be slideable in a magazine fixed and/or a base part fixed slide guide relative to the base part. By this means it is achieved that the slide magazine can be opened for the refill process by sliding of the cap part over the rearward transverse axis.
A preferred embodiment of the invention envisions that the locking mechanism is formed as a detent mechanism between the staple magazine and cap part or magazine cover. The detent mechanism can include a key or push-button device manually operable directly or indirectly via the cap.
A preferred embodiment of the invention envisions that the slide guide includes at least one guide slot on the side of the magazine, with which the cap part, and/or a magazine cover connected thereto fixed against sliding, engages with at least one driver-side slide block or projection. The driver-side slide blocks are thereby preferably formed as pins, journals or tabs projecting sideways beyond the magazine cover, which extend or engage into the guide slots, which are inwardly open. The guide slots preferably include a slide segment oriented parallel to the slide direction and an end segment oriented parallel to the push direction of the driver, wherein the slide segment can transition into the end segment via a detent curve.
A further advantageous embodiment of the invention envisions that the slide guide includes at least a cap-side guide slot, in which at least one, preferably provided spaced apart radially from the pivot axis, base-part-side or magazine-side slide block engages. The cap-side guide slot thereby preferably exhibits a slide segment and a pivot segment, with the slide segment extending parallel to the slide direction and with the pivot segment contiguous therewith and which, when the cap is in the operating position, is oriented concentric to the pivot axis. The pivot segment insures that the cap part and the staple magazine are pivotable together about the pivot axis of the base part into a tacking position. For this purpose, on the base part there can be provided guide and securing groves lying diametrically oppositely to each other with respect to the pivot axis, and provided with the same radial separation from the pivot axis. In order to make possible an opening of the staple magazine by sliding of the cap part, the guide slot in the area of the pivot segment exhibits a transverse axis facing flank open on one side against the slide direction.
According to a further advantageous embodiment of the invention the magazine cover, with the cap part in the operating position, is lockable on the staple magazine preferably with the aid of a latching or detent mechanism. Further, the cap part in the operating position is engaged on the staple magazine limitedly pivotable, with respect to the magazine cover, in the punch direction of the driver against the force of a spring.
A further advantageous embodiment of the invention envisions that between the driver side end of the cap part or the magazine cover on the one hand, and the staple pusher on the other hand, a pull spring is provided, which for example can be constructed as a helical spring or as roll or coil spring. By this means it is achieved that the cap part together with the, in certain cases, slack or de-tensioned pull spring, and the staple pusher can be slid rearward into the loading position. Thereby it is achieved that no spring force acting in the direction of the closing position, which could represent a danger of injury, acts upon the cap part while in the loading position. Accordingly, the cap part does not need to be arrested to the base part when in the loading position, which would be necessary for example in the case of the conventional upper-loading staple device.